RE: [PATCH 1/2] mmc: core: fix permanent sleep of mmcqd during card removal

[Seungwon Jeon <tgih.jun@samsung.com>]

Hi Konstantin.

Could you check this patch with [2/2]?
[PATCH 2/2] mmc: block: don't start new request when the card is removed

mmcqd is often sleeping with acquiring the claim(mmc_claim_host) when a card is removed.
As a result, mmc_rescan can be blocked for the insertion of a card newly. It's a dead lock.

Thanks,
Seungwon Jeon

On Tuesday, January 22, 2013, Seungwon Jeon wrote:
> This patch is derived from 'mmc: fix async request mechanism ...'.
> According as async transfer, a request is handled with twice mmc_start_req.
> When the card is removed, the request is actually not issued in the first
> mmc_start_req [__mmc_start_data_req]. And then mmc_wait_for_data_req_done
> will come in the next mmc_start_req. But there is no event for completions.
> wake_up_interruptible is needed in __mmc_start_data_req for the case of
> removed card.
> 
> Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
> ---
>  drivers/mmc/core/core.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
> index 8b3a122..997b257 100644
> --- a/drivers/mmc/core/core.c
> +++ b/drivers/mmc/core/core.c
> @@ -350,6 +350,7 @@ static int __mmc_start_data_req(struct mmc_host *host, struct mmc_request *mrq)
>  	mrq->host = host;
>  	if (mmc_card_removed(host->card)) {
>  		mrq->cmd->error = -ENOMEDIUM;
> +		mmc_wait_data_done(mrq);
>  		return -ENOMEDIUM;
>  	}
>  	mmc_start_request(host, mrq);
> --
> 1.7.0.4